Collaborative Research: Testing Arctic Ice Sheet Sensitivity to Abrupt Climate Change

合作研究：测试北极冰盖对气候突变的敏感性

• 批准号: 1418040
• 负责人: Gifford Miller
• 金额: $ 28.13万
• 依托单位: University of Colorado at Boulder
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1418040&HistoricalAwards=false
• 关键词: Collaborative; Research; Testing; Arctic; Ice

A team of investigators proposes to investigate the response of the Laurentide and Greenland Ice Sheets to two short term cooling events (several decades to a few centuries in duration) that occurred 9.3 and 8.2 thousand years ago. Assessing the sensitivity of ice sheets to short term climate variability is at the forefront of the scientific community's and the public's interest because short term ice sheet change will drive 21st century sea level rise. Thus a central question of the proposed work is whether ice sheets react abruptly to climate forcings, or are multi-millennial-scale trends in climate required to elicit a large-scale ice sheet response?The investigators propose an intensive field-based research program capitalizing on their newly published work reconstructing ice sheet change using high-precision beryllium-10 dating to test the hypothesis that prominent moraine systems marking former ice extents in West Greenland and Baffin Island record the synchronous advance of the Greenland and Laurentide ice sheets driven by the abrupt cooling events 9.3 and 8.2 thousand years ago. Pilot data reveal that portions of the ice sheet margin that are in contact with the surrounding ocean are able to respond rapidly to a short-lived climate perturbation. To test whether these documented changes were restricted to solely the most sensitive marine-terminating ice sheet sectors, or whether ice sheets are capable of a larger scale response to centennial-scale climate change, well-constrained chronologies of ice sheet change are needed from other regions. The investigators' research objectives are to 1) establish how land-terminating regions of ice sheets, which are more representative of broader ice sheet margins, respond to abrupt climate change, 2) further evaluate the role that oceanic forcing plays in modulating ice sheet response to short-lived climate perturbations, and 3) reconstruct the early Holocene behavior of mountain glacier systems (a proxy for summertime temperature) to evaluate what climatic conditions influenced the ice sheets. The investigators will work to make results easily accessible to the public. The work is led by an early career investigator and will support two graduate and several undergraduate students.

一组调查人员建议调查劳伦德（Laurentide）和格陵兰（Greenland）冰盖对两次短期冷却事件的反应（持续时间数十年到几个世纪），这发生在9.3和82000年前。评估冰盖对短期气候变异性的敏感性位于科学界和公众的兴趣的最前沿，因为短期冰盖变化将推动21世纪的海平面上升。因此，提出的工作的一个核心问题是，冰盖是对气候强迫的反应突然反应，还是在气候中需要多年千年级趋势，以引起大规模的冰盖响应吗？研究人员提出，基于强化的现场研究计划资本利用其新出版的工作冰层使用高级冰冰的越野范围来进行竞争，以确保越来越多的冰冰既有竞争力，以确保越来越多的冰冰，以确保越来越多的冰冰，以验证越来越多的冰冰，以确保越来越多的越野范围的既有越来越多的冰淇淋，以确保越来越多的越野范围的既有越来越多的冰淇淋，以确立越来越多的冰冰的范围。巴芬岛（Baffin Island）记录了由9.3和82000年前突然的冷却事件驱动的格陵兰和劳伦德冰盖的同步进步。飞行员数据表明​​，与周围海洋接触的冰盖边缘的一部分能够迅速响应短暂的气候扰动。为了测试这些记录的变化是否仅限于最敏感的海洋终止冰盖部门，或者冰盖是否能够对百年纪念尺度气候变化做出更大的响应，从其他地区则需要对冰纸的变化良好的时间表。研究者的研究目标是1）确定冰盖的土地终止区域如何代表更广泛的冰片边缘，对突然的气候变化做出响应，2）进一步评估海洋强迫在调节冰冰响应中的作用，使冰纸调节短期寿命的扰动响应，以及对气候越来越多的山地态度（3）对山地的早期造成的影响（3）对山地的影响（3）构建山地胶合体的影响（3）冰盖。调查人员将努力使公众容易获得结果。这项工作由早期职业调查员领导，将支持两名研究生和几名本科生。